Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already establish readOnlyHint=true, but the description adds genuine behavioral context beyond that: default ordering ('newest first'), the conversion-state lifecycle, and the fields returned per referral. It does not mention pagination behavior or rate limits, but with annotations covering safety this is solid.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

One front-loaded sentence stating resource, scope, ordering, return fields, and filters, followed by the underlying endpoint. Every clause carries information; nothing is padded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description usefully names the returned fields (conversion state, customer, link), and pagination parameters are documented in the schema. It is nearly complete for a 9-parameter read tool, though it omits pagination/ordering caveats.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so every parameter is already documented in the schema; baseline is 3. The description restates the filter categories and adds minor meaning (e.g., conversion states), but adds little beyond what the schema already provides.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('List referrals') and immediately defines the resource as 'visitors who arrived via an affiliate link', which distinguishes it from siblings like list_affiliates or list_commissions. The tool's scope and identity are unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It enumerates available filters (affiliate, state, email, Stripe customer, updated-at window), which implies when to use it for scoped queries, but gives no explicit when-to-use/when-not guidance or naming of alternatives among the many sibling list/get tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.